It sounds like they're linking to you because they like your site and want to recommend it to their readers, which is just the sort of link Google likes. Yes, they're run-of-site links, but of the sort that's normal, as opposed to "sponsor" links in the footer or something that's hidden in the source code of every page but never displays. Unless there's something spammy about the site, I don't see a reason to think it's the cause of your problems.

yeah I had the same issue - dont worry about it. If its from a crap site then sure, do something about it but otherwise its natual I reckon. Some wordpress themes and RSS feeds, Twitter Feeds etc can all syndicate content and URLS throughout a site.

I'm dealing with the issue of links coming from blog themes these days -- a few thousand sites, very few of which are in any way related to the site I'm working on, all linking to us from the footer of every page. All because someone who used to work on the site had a bright idea...